1. Field of the Invention:
The present invention relates to safety ski bindings and has specific reference to a heel hold-down device or retainer therefor--that is, a device adapted to hold down the heel portion of a ski boot engaged in the binding and locked in the skiing position between the heel device and a toe or stop member disposed at the front end of the ski binding.
This invention relates more particularly, among heel hold-down or retaining devices known in the art, to those comprising a fixed body locked in an adjustable position on the top surface of the ski and a sole engaging member pivoted to the body and comprising in a known fashion a tongue adapted to lock the binding with the assistance of the boot heel, and a pair of lateral arms or jaws overlying the tongue and surrounding partially the edge of the ski boot sole, so that, whent he sole engaging member is tiled upwards about a transverse axis located at the rear with respect to the heel, the heel can be raised together with the sole engaging member and released from the binding. During this movement, the ski boot is caused to pivot about a fictitious axis adjacent the toe end thereof so as to cause the rotation of the sole engaging member against the force of the spring means constantly urging the sole engaging member to its operative position. The sole engaging member is associated with a control level which, when actuated by the skier, causes this member to pivot upwards and thus release the boot heel as mentioned hereinabove. On the other hand, in case of fall, notably a forward fall, of the skier, during which the skier heel is also moved upwards, the sole engaging member can likewise pivot against the force of resilient means enclosed in the fixed body, so that, when a predetermined release threshold is overstepped, the heel will again be released from the heel hold-down or retaining device.
2. The Prior Art
Many forms of embodiment of heel hold-down or retaining devices of this general type are already known in the art. In most cases, the pivotal movement of the heel engaging member takes place against the resilient force of a spring-loaded mechanism enclosed and mounted in the fixed body, or bearing against it. In this case, the sole retaining member is guided during its upward movement by causing a cross member or a pair of external pivot-pins carried by the sole retaining member to slide in curved recesses or against a ramp of suitable contour formed in or on the fixed body. Moreover, and according to an arrangement also well known in the art, the axis about which the sole retaining member pivots on the fixed body is movably mounted in an elongated groove formed in the fixed body, so that the pivotal movement of the sole retaining member is attended by a substantially axial movement of the side retaining member in conjunction, according to cases, with a forward or backward movement of the sole retaining member with respect to the longitudinal axis of the ski. An arrangment of this character is disclosed notably in the French Pat. No. 2,021,055 or in the published German Pat. Nos. 2,659,369 and 2,027,412.
Now these devices are generally complicated, notably because, during the pivotal movement of the sole retaining member, the spring of the resilient mechanism is also exposed to a certain degree of backlash or deflexion following the movement of the sole retaining member, which is detrimental to a proper mechanical operation and a long useful life. Moreover, it is rather difficult to assembly the component elements of a heel hold-down device of this type without jeopardizing its fluid-tightness, which is absolutely necessary to prevent the ingress of water, snow, or ice, which would be detrimental to the proper operation of the moving parts.